Page 5 of 5

Posted: Thu Apr 23, 2009 1:58 pm
by Hotwired
Maybe I'll take a clip of it. It is corded by the way.

I put my mouse up so I could see the red laser light at the bottom - over the other side of my 75cm deep desk and the circuit over at my side.

The light flickered and occasionally pulsed to full beam - which it is only meant to do when it's in very close proximity to a surface so you cant damage your eyes with the full laser beam if you lift it up.

The laser light kept on flickering while the circuit was on and when the circuit was turned off the mouse light went dead.

It comes back to life if unplugged and reconnected.

I'm just out of space somewhat for somewhere for my mouse to hide while I fiddle with the circuits. Unless I toss it off the other side of the desk every time...

Posted: Thu Apr 23, 2009 2:29 pm
by jimmy101
Hotwired:

Fire up the sound recorder on your PC and record the RF the sparker makes as it cycles?

The first radio transmitters were just spark gaps. A spark creates a ton of RF. That RF should be easily picked up by your sound card, probably don't even need a microphone. (Clearly your mouse is picking up the RF)

Or, turn on a radio and see if you can tune in the RF from the sparker. Feed the audio from the radio into your soundcard for recording and analysis.

Audacity would be good for analysis, or get a copy of WinScope (http://www.zelscope.com/). WinScope includes an FFT function (and a storage scope function) so you can get to the operating frequency directly.

Looking forward to a detailed how-to on your setup :D

Posted: Wed May 13, 2009 10:29 am
by THUNDERLORD
Another possible component I forgot to mention, and was wondering about for some time is the Cold heat solder tool . IDK because they claim "heats instantly" but that still probably isn't fast as a spark gap.
Wonder how they work(?)...

Oh, on the cell phone story I mentioned, The sales girl actually said, " well you should get a newer phone also because the old 800 (+) megahertz could cause cancer"...and I was thinking "WTF, your old phones cause cancer so I should buy your new one's????"

I do recall a story about criminals using the old high mega-hertz cell phones to send signals onto magnetic card reader strips as a component to make withdrawals from certain three initial machines...

I am more interested in the batteries and chargers.
And whether the camera from used phones would be a useful night vision component.(?)
And also a way to transmit from one to another without broadcasting to the world for a personal security or spy cam.(?)
Ever since I saw a full recycle bin of them in the lobby of a college doritorium. :wink: 8)

Posted: Wed May 13, 2009 1:22 pm
by Hotwired
Cold heat is just a forked tip that is shorted out through the solder and component you want to solder.